Under deoxygenated (or partially deoxygenated) conditions, deoxyHb S polymers form parallel-oriented fiber bundles[55], or "fascicles" [62]. The fascicles form because deoxyHb S has a very low solubility in intact RBCs, and insoluble deoxyHb S either initiates or facilitates a change in the cytoskeleton of certain subpopulations of RBCs[55].
